Samantha Shires, a middle-school social studies teacher in Guilford County, North Carolina, wants her students to understand that history doesn't unfold in a series of unrelated events. "History is messy and chaotic," she says. "Students need to see how events are connected and interrelated."

ChronoZoom, a free tool developed by Microsoft Research and an international team of collaborators, is helping her students visually explore the history of, well, just about everything, from the Big Bang right up to the present day.

The open source tool turns the vast history of the universe -- 13.8 billion years of information -- into an interactive, visual timeline. Features enable users to zoom in and out as they explore curated content about, for example, the history of life on Earth, extinction of the dinosaurs, or causes of World War I. Users also can author and share their own timelines about specific events or eras.

"ChronoZoom breathes life into history," says Shires. She creates timelines to introduce units about everything from the Age of Exploration to World War I. She also uses the tool "to let my students create history as they see it. They can put words and pictures to stories from the past and show me what they think is important." Since introducing ChronoZoom in her classroom, she adds, "I can't tell you how many students have told me they always found history boring before. Now it's making sense to them. They see how different aspects of the past align."

Teaching Big History

Inspiration for ChronoZoom came from a geology classroom at the University of California Berkeley. Professor Walter Alvarez, who was among the first to theorize that an asteroid caused mass extinction of the dinosaurs, has long been an advocate of teaching "big history."
That means helping students understand major events that have shaped the cosmos and see relationships across disciplines.

One of the challenges of Big History is grappling with the differences in time scale between, for example, the Earth's geological record (5 billion years), human prehistory (3 million years), or history of civilization (about 5,000 years). To make sense of these time scales, one of Alvarez's students suggested creating a giant digital canvas to represent the history of the cosmos and then using a tool like Adobe Photoshop to zoom in and out.

It was an intriguing idea but fraught with technical challenges. Donald Brinkman, program manager for Microsoft Research, says zooming from the Big Bang to the present day "requires a zoom level of about 500 trillion percent. Photoshop, amazing as it is, has a maximum zoom of about 4,625 percent." His team took up the challenge and brought in collaborators from around the globe to develop the current version of ChronoZoom and related resources for the classroom. Partners, in addition to UCB, include University of Washington, Learn NC, Moscow State University in Russia, National Council of the Social Studies, and American Historical Association.

To make the tool as accessible as possible, it's designed to work on all browsers and on practically any device, including mobiles and tablets. No downloads are required. You can listen to Professor Walter Alvarez explain the thinking behind ChronoZoom in this lecture.

Matching the Tool to the Classroom

Along with addressing technical challenges, the ChronoZoom team wanted to make sure the new tool "would get into classrooms and empower educators to use it effectively alongside their other tools for teaching," Brinkman says.

Shires is one of the educators who consulted on ChronoZoom, providing "real-life feedback," she says. "Can we really use this in the classroom? Is it applicable to what we're trying to teach?"

Brinkman says feedback from teachers and students informed tool design, including suggestions for features that software engineers might not have imagined. Shires, for instance, sees great potential for teacher collaboration, both across subject areas and from different locations in the world.

Along with providing user feedback, Shires also collaborated on development of one of three units aligned to the Common Core State Standards. She worked on a unit that uses ChronoZoom to teach about the causes of World War I. Another ready-to-use lesson, called Atlantic Encounters, explores collisions between cultures, challenging students to think about causes and consequences of past events. A third unit, ChronoZoomers Guild, challenges students to take on time-travel missions and, potentially, alter the course of human history.

Classroom materials are intended to help educators "teach historical thinking," Brinkman says. All are free to download and available for teachers "to mash up however they want."

ChronoZoom was showcased at a recent conference of the National Council of the Social Studies. More outreach is planned in the coming months to introduce teachers to the tool and classroom resources, including a workshop at SXSWedu in March.

Meanwhile, watch for ChronoZoom content to expand as users design their own timelines and add additional content. "So far, we have between 6,000 and 7,000 content items," Brinkman estimates. That includes photos, videos, research papers, short text, and a variety of primary source documents, most of which has been curated by graduate students and subject-area experts. "Our ultimate goal," he says, "is to create a visual Wikipedia history of everything."